Nitrous Oxide Anesthetic Administration System

ABSTRACT

The present invention is a method and system for administering nitrous oxide. The system includes a fluid control system for controlling the flow of nitrous oxide and oxygen to the patient. A nitrous oxide and oxygen supply, vacuum source, a breather bag, and a nasal delivery interface system are fluidly connected to the fluid control system and a patient. The fluid control system also includes a safety scavenge system including a mass airflow sensor, master controller, nitrous oxide valve, and alarm. The mass airflow sensor reads the scavenging vacuum pressure which it communicates to the master controller. Depending upon the scavenging vacuum pressure, the master controller can activate an alarm or shut off the flow of nitrous oxide. In operation, the present invention provides a system for administering anesthesia/analgesia gas which prevents excessively high volumes of exhaled nitrous oxide in the operatory environment through monitoring of the scavenge vacuum pressure.

CROSS REFERENCE TO RELATED APPLICATIONS

This continuation application is related to and claims priority fromearlier filed continuation-in-part application Ser. No. 12/890,176 filedSep. 24, 2010, non-provisional patent application Ser. No. 12/567,729filed Sep. 25, 2009, and provisional patent application Ser. No.61/100,149, filed Sep. 25, 2008, all of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

The present invention relates to a system for administering gas. Moreparticularly, the present invention relates to a system foradministering anesthesia/analgesia gas which provides convenient, directaccess by a medical practitioner, a clear line of vision for the medicalpractitioner, and flexibility to accommodate the patient and medicalprofessional's needs.

N2O analgesia has been used for over a century to successfully relax andsedate dental patients. Originally and until recently the application ofthese gages was virtually unrestricted and thus the supply systemrequired was relatively unencumbered. With the advent of mandatoryscavenge systems for nitrous delivery, these units became much morebulky and difficult to use in day to day practice and this utilized ratedeclined.

Typically, the compressed medical gages are delivered to thepractitioner's facility in gas cylinders. These cylinders either connectto a central distribution system, serving multiple operating rooms, orthey are portable and are mounted on rolling carts which serve oneoperating room and patient. These cylinders are connected via hoses orpiping to a regulating system which controls delivery pressure, flowrate and blended ratio. There are monitors, gages and other devices toprovide information to the practitioner regarding the deliveryparameters. From the control device, gas flows via flexible hoses to anasal delivery interface device. As shown in FIG. 1, vacuum scavengingof expelled gases flows from the nasal delivery interface device, viaflexible tubing, into the centralized building vacuum utility system.

These essential components are incorporated into support systems.Systems commonly found in the art fall into three general categories: a)cart mounted tanks and controls, b) cart mounted controls and c) wall orstationary cabinet mounted controls.

Cart mounted tanks and control systems utilize an open or closed,wheeled cart. (FIGS. 4, 9). Portable O2 and N2O tanks are mounted on thecart. The control system and breather bag are usually mounted on acenter pole attached to an open cart or supported by the shell of anenclosed cart. The patient supply tubing connects the cart outlet to thenasal delivery interface device. Referring to FIG. 2, the scavengingtubing connects the nasal delivery interface device via flexible tubinginto the centralized building vacuum utility system.

As illustrated in FIGS. 1-2, current systems running from the controldevices to the nasal delivery interface device use multi lumen hosesystems which are long, heavy, complex and somewhat stiff. They pull onthe patient's head and limit practitioner accessibility to the patient'smouth area. As a result they also limit the ability of the practitionerto reposition the patient's head.

Cart mounted control systems are similar to those above, except that theO2 and N2O are supplied from a central source via floor or wall gasoutlets rather than from in situ tanks. Flexible hoses route the gasesfrom the outlet to the control system. The control system and breatherbag are mounted on a center pole attached to an open, wheeled cart. Thepatient supply tubing connects the cart outlet to the nasal deliveryinterface device. The scavenging tubing connects the nasal deliveryinterface device via flexible tubing into the centralized buildingvacuum utility system.

As illustrated in FIG. 3, wall and cabinet mounted systems have the O2and N2O gas supplied via flexible or rigid tubing from a central source.This tubing is enclosed in the walls of the operatory with othercentralized utilities. The control system and breather bag are mountedto the wall or cabinet unit. The mounting may be a flush mount, surfaceor articulated arm mount design. Long patient supply tubing connects thecontrol systems to the nasal delivery interface device on the patient.Long scavenging system tubing connects the nasal delivery interfacedevice into the centralized building vacuum utility system.

Also, wall mounted systems are typically separated from the patientchair by a work surface or passageway. Wall mount systems have long hoselengths between the control devices and the nasal delivery interfacedevice. The longer the hose length, the longer the latency periodbetween changing a control setting and the patient actually receivingthat changed gaseous output. In addition, the hose position and lengthinterferes with operator positioning. Tubing runs from the wall mounted,control system outlet to the nasal delivery interface device. Thistubing crosses a passageway or work surface and blocks or encumberswhich ever of these it traverses.

As illustrated in FIGS. 4-8, cart mounted systems can be located behindone of the practitioners or tucked under the back of the patient chair.In either case, visual monitoring of critical information in impeded.This is a dangerous situation because unknown changes occurring in thegaseous anesthetic system can be detrimental to the patient.Additionally, excess gas expelled into the operatory is harmful to thepractitioners.

Also, carts located in the passageways, or workplace around the patientchair, cause inference as the practitioners move around the patient.Staff can trip over the carts and be injured and the flow of othertechnology and emergency access is impeded. As well as the cost ofdamaging an anesthetic system, rupturing any high pressure, 2000 psi,system can be very dangerous to all occupants of the operatory.

There are two main drawbacks of the systems describe above. First,current systems usually put the system controls out of direct reach ofthe medical professional when he/she is seated in normal treatmentpositions. This limitation is especially burdensome with wall mountedsystems. This makes it difficult for the medical professional toaccomplish anesthetic system adjustments without walking around orreaching around the patient. This awkward arrangement slows access andresponse to emergency situations. Second, current systems often putmonitoring device displays and gauges out of direct view of the doctorand assistant.

Therefore, it would be particularly desirable to provide a system ormethod for anesthesia/analgesia gas delivery provides a nitrous oxideanesthetic administration system which provides convenient, directaccess by a medical practitioner, a clear line of vision for the medicalpractitioner, and flexible to accommodate the patient and professional'sneeds. Currently, there is no known nitrous oxide anestheticadministration system in the prior art which provides these benefits.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention preserves the advantages of priorart nitrous oxide anesthetic administration systems or methods. Inaddition, it provides new advantages not found in currently availablenitrous oxide anesthetic administration systems or methods and overcomesmany disadvantages of such currently available nitrous oxide anestheticadministration systems or methods.

The present invention is a system for administering nitrous oxide whichis preferably attached to a patient chair. The system generallyincludes: a mounting surface structure, a fluid control system attachedto the mounting surface structure, a nasal delivery interface systemconnected to a patient and fluid control system, a nitrous oxide andoxygen supply connected to the fluid control system, a vacuum source forscavenging, a breather bag connected to the fluid control system, amounting plate assembly to interface with patient or dental chairs, anadjustable post mechanism attached to the mounting plate assembly andthe mounting surface structure, supply gas connectors and mixed gasoutput connectors attached to the fluid control system, and otherhardware and tubing that is necessary to administer nitrous oxide in ahealth care environment, preferably a dentist's office.

The system includes an adjustable post mechanism attached to a patientor dental chair. The adjustable post mechanism is attached to a mountingplate assembly which is attached to a lower portion of a patient chair.The adjustable post mechanism is configured for height adjustment andpivotal adjustment to provide convenience of use to a practitioner.

The mounting surface structure includes a top surface and a bottomsurface. The bottom surface of the mounting surface structure isattached to a top end of the adjustable post mechanism. The mountingsurface structure positioned along a horizontal axis or approximately180 degrees. The mounting surface structure attached to a breather bag aproximal end and a fluid control system at a distal end closest to apractitioner.

A fluid control system for controlling the flow of nitrous oxide andoxygen is attached to the mounting surface structure. The fluid controlsystem including a fluid flow meter mounted on a top surface of thefluid control system. A display of the fluid flow meter positioned alonga vertical axis at less than 90 degrees relative to the mounting surfacestructure to provide a better view to the practitioner. A nitrous oxideand oxygen supply fluidly connected to the fluid control system usingfluid connectors fixedly attached to the bottom surface of said mountingsurface structure.

A nasal delivery interface system fluidly connected to the fluid controlsystem. The nasal delivery interface system including a singlescavenging tube and a single nitrous oxide and oxygen tube fluidlyconnected to a single nasal delivery mask. The fluid control systemincluding a mixed gas output connector fluidly connected to the singlenitrous oxide and oxygen tube. A vacuum source fluidly connected to thesingle scavenging tube for scavenging excess gases and the fluid controlsystem.

A breather bag is vertically mounted to a top surface of the mountingsurface structure. The breather bag positioned along a vertical axis orabout 90 degrees depending upwardly from the mounting surface structure.The breather bag mounted rearward or behind of the fluid control systemto allow full view of fluid flow meter display. The breather bag fluidlyconnected to the control system by way of an elongated tubular structureattached to a front surface of the fluid flow meter.

The fluid control system also includes a safety scavenge systemincluding a mass airflow sensor, master controller, nitrous oxide valve,and alarm. The mass airflow sensor reads the scavenging vacuum pressurewhich it communicates to the master controller. Depending upon thescavenging vacuum pressure, the master controller can activate an alarmor shut off the flow of nitrous oxide. In operation, the presentinvention provides a system for administering anesthesia/analgesia gaswhich prevents excessively high volumes of exhaled nitrous oxide in theoperatory environment through monitoring of the scavenge vacuumpressure.

The safety scavenge system more specifically includes the followingcomponents. The mass airflow sensor for reading scavenging vacuumpressure is fluidly connected to the scavenging tube before the vacuumsource. The master controller in electrical communication with the massairflow sensor for receiving the scavenging vacuum pressure reading fromthe mass airflow sensor which is compared to a predetermined range. Avisual alarm is in electrical communication with the master controllerwhich instructs the visual alarm to activate if the scavenging vacuumpressure is less than a first predetermined range. An audio alarm is inelectrical communication with the master controller which instructs theaudio alarm to activate of the scavenging vacuum pressure is less than asecond predetermined range. A nitrous oxide valve is fluidly connectedto the nitrous oxide supply and in electrical communication with themaster controller which shuts off the nitrous oxide shut-off valve whenthe scavenging vacuum pressure is less than a third predetermined range.

In operation, the present invention provides a system for administeringanesthesia/analgesia gas which provides convenient and direct access toa medical practitioner. The practitioner connects the nasal deliveryinterface system to the patient and to the fluid control system. Afterthe nasal mask is attached to the patient, the nitrous oxide/oxygen gasis turned on and the gas enters a single tube fluidly connected with anasal delivery mask. Throughout the administration of the gas, thesystem allows the practitioner a direct view and a close proximity tothe upright breathing bag, fluid control system including display,patient, and all other parts of the nitrous oxide administration systemwhich makes the administration of the gas much more efficient, safe, andless time consuming. Also, the mounting of the nitrous oxide anestheticadministration system to a patient's chair provides greater stabilityand convenience to a practitioner.

When the vacuum source is operational, any excess gases are scavengedfrom the patient through the nasal delivery mask, along a singlescavenging tube, and returns back through the fluid control system. Byonly having two tubes, the patient and practitioner are given additionalspace and movement and reduce the possibility of entanglement.

In addition, the present invention includes the following method foradministering nitrous oxide to a patient. First, a fluid generated by avacuum source is provided. Second, nitrous oxide fluid from a nitrousoxide source is provided. Third, a means for scavenging excess nitrousoxide is in fluid connection with the nitrous oxide source and thevacuum source. Fourth, a safety scavenge system is connected to thefluid connection between the nitrous oxide source and the vacuum source.The safety scavenge system includes a mass airflow sensor, mastercontroller, alarm, and nitrous oxide valve. Fifth, the means forscavenging excess nitrous oxide is connected to the vacuum source andthe nitrous oxide source onto a patient. Sixth, a flow rate flow rate ofthe vacuum source is increased to provide fluid into the safety scavengesystem. Seventh, nitrous oxide is released through the safety scavengesystem upon the vacuum source reaching a predetermined range. Eighth,excess nitrous oxide is retrieved from the means for scavenging excessnitrous oxide using the vacuum source. Ninth, the vacuum source isdecreased below the third predetermined range which prevents the safetycontrol valve from releasing nitrous oxide. The safety scavenge systemactuated by flow fluids to control the release of nitrous oxidetherethrough.

It is therefore an object of the present invention to provide a methodor system for a nitrous oxide anesthetic administration system whichprovides convenient access to nitrous oxide for a practitioner andpatient.

It is a further object of the present invention to have direct access tothe fluid control system and patient during administration of thenitrous oxide.

It is also an object of the present invention to provide a clear line ofvision for the medical practitioner and flexibility to accommodate thepatient and practitioner's needs.

Another object of the present invention is to eliminate the problemsassociated with current nitrous oxide delivery and scavenging systems.

Furthermore, another object of the present is to provide greater safetyto patients and medical or dental persons during release of nitrousoxide in a medical or dental office.

A further object of the present invention is to provide a system foradministering anesthesia/analgesia gas which prevents excessively highvolumes of exhaled nitrous oxide in the operatory environment throughmonitoring of the scavenge vacuum pressure

Other objects, features and advantages of the invention shall becomeapparent as the description thereof proceeds when considered inconnection with the accompanying illustrative drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are characteristic of the nitrous oxideanesthetic administration systems and methods are set forth in theappended claims. However, the nitrous oxide anesthetic administrationsystems and methods, together with further embodiments and attendantadvantages, will be best understood by reference to the followingdetailed description taken in connection with the accompanying drawingsin which:

FIG. 1 is a prior art nitrous oxide anesthetic administration system;

FIG. 2 is prior art nasal delivery interface device;

FIG. 3 is a prior art wall mounted nitrous oxide anestheticadministration system;

FIG. 4 is a prior art cart mounted nitrous oxide anestheticadministration system;

FIG. 5 is a prior art cart mounted nitrous oxide anestheticadministration system;

FIG. 6 is a prior art cart mounted nitrous oxide anestheticadministration system of FIG. 5;

FIG. 7 is a prior art cart mounted nitrous oxide anestheticadministration system of FIG. 5;

FIG. 8 is a prior art cart mounted nitrous oxide anestheticadministration system of FIG. 5;

FIG. 9 is a prior art nitrous oxide anesthetic administration system;

FIG. 10 is a left side view of the nitrous oxide anestheticadministration system of the present invention;

FIG. 11 is a right side view of the invention of FIG. 10;

FIG. 12 is front perspective view of the invention of FIG. 10;

FIG. 13 is a partial left side view of the invention of FIG. 10;

FIG. 14 is a left side view of the invention of FIG. 10;

FIG. 15 is a rear perspective view of the invention of FIG. 10;

FIG. 16 is a sample of prior art dental chairs which can be utilizedwith the present invention;

FIG. 17 is a close-up view of a bottom portion of the present invention;

FIG. 18 is close-up view of gas connectors used with the presentinvention;

FIG. 19 is a front perspective view of the present invention; and

FIG. 20 is a schematic illustration of another embodiment of the presentinvention which includes a safety scavenging system.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIGS. 10-19, a nitrous oxide anesthetic administrationsystem 10 of the present invention is shown. The present invention is anitrous oxide administration system 10 which provides convenient, directaccess by a medical practitioner, a clear line of vision for the medicalpractitioner, and flexibility to accommodate the patient and medicalprofessional's needs.

It should be understood that this invention is well suited andpreferably used in a dental office environment; however, it may be usedin any environment where delivery of objects to a work area is desired.The invention will be disclosed herein in connection with a dentaloffice environment; however, the present invention is not intended to belimited to that particular use and may be used in any health caresetting or any setting where a nitrous oxide is required. Theconfiguration of the system components may vary depending on variationsin the patient chair, physical site constraints and on the needs of aparticular dental practice

Most importantly, the nitrous oxide administration system 10 includes amounting surface structure 20 and adjustable post mechanism 30 which ismounted directly to a patient chair 500 using a mounting plate assembly40. A system for delivering nitrous oxide is attached to the mountingsurface structure 20 or adjustable post mechanism 30 to provideconvenient and direct access to the practitioner for delivering thenitrous oxide to the patient, which will be further explained herein.

The nitrous oxide anesthetic administration system may include someelements of prior art nitrous oxide delivery systems. For example, itmay include a low-vacuum fluid generated by a vacuum source, a nitrousoxide fluid provided by a nitrous oxide source, and a scavenging mask.In addition, the nitrous oxide safety system may also include an oxygensource, mixing valve, flow meter, breathing bag, and tubing or lines.Note, the nitrous oxide anesthetic administration system of the presentinvention may also include elements of the system disclosed in “NitrousOxide Safety System” (Non-Provisional patent application Ser. No.12/398,783 filed Mar. 5, 2009).

Referring to FIG. 1, the present invention is a system for administeringnitrous oxide 10 which is preferably attached to a patient chair 500.The system generally includes: a mounting surface structure 20, a fluidcontrol system 50 attached to the mounting surface structure 20, a nasaldelivery interface system 60 connected to a patient and fluid controlsystem 50, a nitrous oxide and oxygen supply (not shown) fluidlyconnected to the fluid control system 50, a vacuum source (not shown)for scavenging excess gases, a breather bag 70 fluidly connected to thefluid control system 50 and mounted to the mounting surface structure 20in a vertical orientation, a mounting plate assembly 40 (FIG. 17) tointerface with patient or dental chairs from multiple manufacturers, anadjustable post mechanism 30 attached to the mounting plate assembly 40and the mounting surface structure 20, supply gas connectors 80A, 80B(FIG. 18) and mixed gas output connector 90 attached to the fluidcontrol system 50, and other hardware, software, lines, and tubing thatare necessary to administer nitrous oxide in a health care environment,preferably a dentist's office.

The system includes an adjustable post mechanism 30 attached to apatient or dental chair 500. The adjustable post mechanism 30 mayinclude a cylindrical post 30A that is both pivotally and heightadjustable within a corresponding sleeve 30B. The post 30A may slidablyengage within the sleeve 30B and may be positioned in a fixed ortemporary position when necessary. The post 30A may be secured into aposition by use of methods known in the art including ratchetingmechanisms or a tightening collar. The adjustable post mechanism 30 isconfigured and arranged for height adjustment and pivotal adjustment toprovide convenience of use to a practitioner.

The adjustable post mechanism 30 is attached to a mounting plateassembly 40 which is attached to a lower portion of a patient chair 500.Referring to FIG. 17, the mounting plate assembly 40 may include a chairattachment structure 42, a base plate 44, and a vertical extensionstructure 46 connecting the chair attachment structure 42 and the baseplate 44. The base plate 44 defines an aperture for receipt of a bottomend of the adjustable post mechanism 30. The base plate 44 is attachedto the adjustable post mechanism 30 with sufficient strength and canaccommodate a wide range of adjustable post mechanisms 30. The baseplate 44 lies along a horizontal axis. The chair attachment structure 42is connected or attached to a bottom or lower portion of a patient chair500 at a proximal end. The chair attachment structure 42, at the distalend, attaches to an extension structure 46 using methods known in theart. The extension structure 46 attaches to the chair attachmentstructure 42 and the base plate 44. In one embodiment, the extensionstructure 46 extends downwardly from the chair attachment structure 42and is secured, at a top end, to the chair attachment structure 42 usinga bolt or other fastener. The base plate 44 then attaches to a bottomend of the extension structure 46. Once the chair attachment structure42, extension structure 46, and base plate 44 are secured to oneanother, they form a mounting plate assembly 40 for possible adaptationto other chairs made by various manufacturers. It should be noted thatthe mounting plate assembly 40 may interface with a variety of patientchairs 500A-E from multiple manufacturers as illustrated in FIG. 16.

The mounting surface structure 20 includes a top surface and a bottomsurface. The bottom surface of the mounting surface structure 20 isattached to a top end of the adjustable post mechanism 30. The mountingsurface structure 20 is positioned along a horizontal axis orapproximately 180 degrees. The mounting surface structure 20 is attachedto the breather bag 70 at a proximal end and a fluid control system 50at a distal end closest to a practitioner.

Referring to FIGS. 14 and 19, a fluid control system 50 for controllingthe flow of nitrous oxide and oxygen is attached to the mounting surfacestructure 20. The fluid control system 50 includes a fluid flow meter 52mounted on a top surface of the fluid control system 50. A display ofthe fluid flow meter 52 is positioned along a vertical axis at less than90 degrees, preferably between 30 degrees to 45 degrees, relative to themounting surface structure 20 to provide a better view to thepractitioner. Referring to FIG. 18, the nitrous oxide and oxygen supply(not shown) is fluidly connected to the fluid control system 20 usingfluid connectors 80A, 80B fixedly attached to the bottom surface of saidmounting surface structure 20. The fluid control system 50 also includesan emergency air intake port.

Referring to FIGS. 12-13, a nasal delivery interface system 60 isfluidly connected to the fluid control system 50. The nasal deliveryinterface system 60 includes a single scavenging tube 60B and a singlenitrous oxide and oxygen tube 60A fluidly connected to a single nasaldelivery mask 62. The fluid control system 500 including a mixed gasoutput connector 90 fluidly connected to the single nitrous oxide andoxygen tube 60A. A vacuum source (not shown) is fluidly connected to thesingle scavenging tube 60B for scavenging excess gases and the fluidcontrol system 50. Note, the vacuum source may be provided by a varietyof methods known in the art.

Referring to FIG. 15, the breather bag 70 is vertically mounted to a topsurface of the mounting surface structure 20. The breather bag 70 ispositioned along a vertical axis or about 90 degrees depending upwardlyfrom the mounting surface structure 20. The breather bag 70 is mountedrearward or behind the fluid control system 50 to allow full view offluid flow meter display 52. The breather bag 70 is fluidly connected tothe control system 50 by way of an elongated tubular structure 72attached to a front surface of the fluid flow meter 52.

In operation, the present invention provides a system for administeringanesthesia/analgesia gas 10 or any type of gases which providesconvenient and direct access to a medical practitioner. The practitionerconnects the nasal delivery interface system 60 to the patient and tothe fluid control system 50. After the nasal mask 62 is attached to thepatient, the nitrous oxide/oxygen gas, or anesthetic, is turned on andthe gas enters a single tube 60A fluidly connected with the nasaldelivery mask 62. Throughout the administration of the gas, the system10 allows the practitioner a direct view and a close proximity to theupright breathing bag 70, fluid control system 50 including display 52,patient, and all other parts of the nitrous oxide administration system10 which makes the administration of the gas much more efficient, safe,and less time consuming. Also, the mounting of the nitrous oxideanesthetic administration system 10 to a patient's chair providesgreater stability and convenience to a practitioner.

In summary, the present invention provides a system for administeringanesthesia/analgesia gas 10 which provides convenient, direct access bya medical practitioner, a clear line of vision for the medicalpractitioner, and flexibility to accommodate the patient and medicalprofessional's needs. The present invention is a novel configurationwhich mounts the control system, monitoring devices, safety devices andbreather bag which mounts directly or indirectly to the patient chair.

Some of the benefits of the proposed novel invention are as follows. Thepresent invention shortens hoses from the fluid control system to thepatient to reduce cost, complexity and weight. The present inventionminimizes control input to nasal delivery interface device output(latency) by at least 50% by shortening hose length. The presentinvention minimizes patient head access limitation and movementrestriction by minimizing hose lengths, stiffness and multiples. Thepresent invention eliminates dual hoses for each of: O2/N2O andscavenge. The present invention puts controls within direct, forwardreach of doctor (from normal treatment position) throughout procedure.The preset invention puts displays and gauges in direct view of doctorand assistant throughout procedure to enhance practitioner and patientsafety. The present invention provides open passage around patient andpatient support chair by eliminating support cart. The present inventionprovides open passage around patient and patient support chair byeliminating tubing crossing passageways. The present inventioneliminates potential of toppling cart and damaging systems byeliminating tubing crossing passageways. The present inventioneliminates the potential danger caused by damaging a high pressure gassystem. The present invention maximizes visibility of breather bag bydoctor and assistant throughout procedure by orienting breather bag, orbellows, superior to inlet rather than current designs which hangbreather bags inferior to their inlet. The present invention reducespatient anxiety prior to their procedure by reducing the visual impactof the anesthetic apparatus. The present invention minimizes systemsize, complexity and cost. The present invention has systemconfiguration adaptable to all operatory configurations. The presentinvention has a system capable of mounting to most commerciallyavailable patient chairs via model specific interface plates. Mostimportantly, the present invention mounts directly to the patient chairto accomplish all of the above.

Now referring to another embodiment of the present invention asschematically illustrated in FIG. 20 which includes a fluid controlsystem 50 having a safety scavenge system 200. The safety scavengesystem 200 includes a mass airflow sensor 210, master controller 220which includes a CPU or processor, nitrous oxide valve 250, and variousalarms 230, 240. The mass airflow sensor 210 reads the scavenging vacuumpressure which it communicates to the master controller 220. Dependingupon the scavenging vacuum pressure and a set of predetermined ranges,the master controller 220 can activate an audio alarm 240, visual alarm230, or shut off the nitrous oxide valve 250. In operation, the presentinvention provides a system for administering anesthesia/analgesia gaswhich prevents excessively high volumes of exhaled nitrous oxide in theoperatory environment through monitoring of the scavenge vacuumpressure.

The safety scavenge system 200 more specifically includes the followingcomponents. It should be noted that the safety scavenge system 200 maybe available within the fluid control system 50 as an internal componentor as a standalone unit attached between the flow meter nitrous oxideinlet and nitrous oxide gas source or supply. The mass airflow sensor210 for reading scavenging vacuum pressure is fluidly connected to thescavenging tube 60B before the vacuum source 100. The master controller220, including a CPU or processor, in electrical communication with themass airflow sensor 210 for receiving the scavenging vacuum pressurereading from the mass airflow sensor 210 which is compared to apredetermined range.

In one embodiment, the predetermined range is related to the AmericanDental Association's recommended 45 LPM (liters per minute) scavengevacuum when nitrous oxide is in use. Typically, if scavenge pressurefalls below the 45 LPM, it will trigger a light or visual alarm (lessthan 45 LPM), audio or audio/visual alarm (less than 25 LPM), or thenitrous oxide flow will be stopped (less than 15 LPM). Of course, thesepredetermined ranges as a triggering point may be adjusted according tothe user's preferences including activating or deactivating certainresponses.

A visual alarm 230 is in electrical communication with the mastercontroller 220 which instructs the visual alarm 230 to activate if thescavenging vacuum pressure is less than a first predetermined range. Anaudio alarm 240 or audio/visual alarm is in electrical communicationwith the master controller 220 which instructs the audio alarm 240 toactivate if the scavenging vacuum pressure is less than a secondpredetermined range. A nitrous oxide valve 250 is fluidly connected tothe nitrous oxide supply and in electrical communication with the mastercontroller 220 which shuts off the nitrous oxide shut-off valve 250 whenthe scavenging vacuum pressure is less than a third predetermined range.

One example of a configuration of the safety scavenge system 200 isillustrated in FIG. 20. The scavenge hose 60B is connected between thenasal mask or hood and the inlet port 90B of the fluid control system50. A dental vacuum is plugged into the outlet port 80B. A portion ofthe flow is diverted through a mass airflow sensor valve 210. Theelectrical output of the mass airflow sensor 210 is sent to a processoror master controller 220 where it is calibrated at LPM flow. Inoperation, the processor output will turn on a warning light 230 whenthe flow falls below 45 LPM. An alarm 240 sounds when flow falls below25 LPM. The nitrous oxide valve is shut off when the flow falls below 15LPM.

In addition, the present invention includes the following method foradministering nitrous oxide to a patient. First, a fluid generated by avacuum source is provided. Second, nitrous oxide fluid from a nitrousoxide source is provided. Third, a means for scavenging excess nitrousoxide is in fluid connection with the nitrous oxide source and thevacuum source. Fourth, a safety scavenge system is connected to thefluid connection between the nitrous oxide source and the vacuum source.The safety scavenge system includes a mass airflow sensor, mastercontroller, alarm, and nitrous oxide valve. Fifth, the means forscavenging excess nitrous oxide is connected to the vacuum source andthe nitrous oxide source onto a patient. Sixth, a flow rate flow rate ofthe vacuum source is increased to provide fluid into the safety scavengesystem. Seventh, nitrous oxide is released through the safety scavengesystem upon the vacuum source reaching a predetermined range. Eighth,excess nitrous oxide is retrieved from the means for scavenging excessnitrous oxide using the vacuum source. Ninth, the vacuum source isdecreased below the third predetermined range which prevents the safetycontrol valve from releasing nitrous oxide. The safety scavenge systemactuated by flow fluids to control the release of nitrous oxidetherethrough.

Therefore, while there is shown and described herein certain specificstructure embodying the invention, it will be manifest to those skilledin the art that various modifications and rearrangements of the partsmay be made without departing from the spirit and scope of theunderlying inventive concept and that the same is not limited to theparticular forms herein shown and described except insofar as indicatedby the scope of the appended claims.

What is claimed is:
 1. A system for administering nitrous oxide to apatient, comprising: a fluid control system for controlling the flow ofnitrous oxide and oxygen; a nasal delivery interface system fluidlyconnected to the fluid control system; a nitrous oxide and oxygen supplyfluidly connected to the control system; a vacuum source fluidlyconnected to the scavenging tube for scavenging excess gases; the fluidcontrol system includes a safety scavenge system, the safety scavengesystem comprising: a mass airflow sensor for reading scavenging vacuumpressure fluidly connected to the scavenging tube before the vacuumsource; a master controller in electrical communication with the massairflow sensor for receiving the scavenging vacuum pressure reading fromthe mass airflow sensor which is compared to one or more predeterminedranges; and a nitrous oxide valve fluidly connected to the nitrous oxidesupply and in electrical communication with the master controller whichshuts off the nitrous oxide shut-off valve when the scavenging vacuumpressure is less than a third predetermined range.
 2. The system ofclaim 1, further comprising: a visual alarm in electrical communicationwith the master controller which instructs the visual alarm to activateif the scavenging vacuum pressure is less than a first predeterminedrange.
 3. The system of claim 1, further comprising: an audio alarm inelectrical communication with the master controller which instructs theaudio alarm to activate of the scavenging vacuum pressure is less than asecond predetermined range.
 4. The system of claim 1, wherein the fluidcontrol system including a mixed gas output connector fluidly connectedto said single nitrous oxide and oxygen tube.
 5. The system of claim 1,further comprising: a means for mounting a fluid control system and abreather bag to a medical chair which provides convenient and directaccess to a medical practitioner, the fluid control system attached tothe means for mounting the fluid control system.
 6. The system of claim1, wherein said nasal delivery interface system includes a scavengingtube and a nitrous oxide and oxygen tube fluidly connected to a nasaldelivery mask.
 7. A method for administering nitrous oxide to a patient,comprising the following steps: providing a fluid generated by a vacuumsource; providing nitrous oxide fluid from a nitrous oxide source;providing a means for scavenging excess nitrous oxide in fluidconnection with said nitrous oxide source and said vacuum source;connecting a safety scavenge system to the fluid connection between thenitrous oxide source and said vacuum source, the safety scavenge systemincluding: a mass airflow sensor for reading scavenging vacuum pressurefluidly connected to the means for scavenging excess nitrous oxide; amaster controller in electrical communication with the mass airflowsensor for receiving the scavenging vacuum pressure reading from themass airflow sensor which is compared to one or more predeterminedranges; and a nitrous oxide valve fluidly connected to the nitrous oxidesource and in electrical communication with the master controller whichshuts off the nitrous oxide valve when the scavenging vacuum pressure isless than a third predetermined range; positioning the means forscavenging excess nitrous oxide connected to said vacuum source and saidnitrous oxide source onto a patient; increasing flow rate of the vacuumsource to provide fluid into the safety scavenge system; releasingnitrous oxide through said safety scavenge system upon the vacuum sourcereaching or exceeding the third predetermined range; and whereby thesafety scavenge system is actuated by fluids to control the release ofnitrous oxide therethrough.
 8. The method of claim 7, furthercomprising: a visual alarm in electrical communication with the mastercontroller which instructs the visual alarm to activate if thescavenging vacuum pressure is less than a first predetermined range. 9.The method of claim 7, further comprising: an audio alarm in electricalcommunication with the master controller which instructs the audio alarmto activate of the scavenging vacuum pressure is less than a secondpredetermined range.
 10. The method of claim 7, further comprising:retrieving excess nitrous oxide from the means for scavenging excessnitrous oxide using the vacuum source.
 11. The method of claim 10,further comprising: decreasing the vacuum source below the thirdpredetermined range which prevents the safety control valve fromreleasing nitrous oxide.